Behavior of corneal endothelial density over a lifetime.

PURPOSE: To define a behavioral model of corneal endothelial density over a lifetime, determine its values, construct a graphic representation, and show the probabilities of occurrence using modified prognosis ranges. SETTING: A private clinic in Brazil. METHODS: This retrospective study comprised 784 corneal specular microscopy examinations without regard to race, sex, or age and without a history or pathologies that would alter the endothelium. Endothelial density results were grouped by decades according to patient age. Projections of mean densities and standard deviations by decade were calculated by adjusting the model by variable. The probability of occurrence of the endothelial densities was calculated (P <.05). RESULTS: The endothelial density over time followed a decreasing linear model (correlation coefficient -0.993). As the endothelial density decreased, the standard deviation tended to increase. The probability of occurrence of an endothelial density of less than 2000 cells/mm(2) was higher from the seventh decade on. CONCLUSIONS: Knowing the representative values of endothelial density and the probabilities of occurrence over a lifetime can help surgeons determine the risk to the cornea of anterior segment surgery. It can also be useful in following eyes with disease affecting the endothelium and in preparing and evaluating corneal specular microscopy reports.

Determination of cadaveric antibody against HIV in vitreous humor of HIV-positive patients: potential use in corneal transplantation.

The authors suggest the determination of antibody against HIV in vitreous humor as a screening technique for AIDS carriers, specially in cases of corneal transplantation when the eye bank could make the examinations required and in cases when drawing blood after death becomes difficult. Ten eyes of patients having died of AIDS-related causes were studied and 100% of the samples tested were found to be positive. False-positive results were eliminated by the study of a group of 90 eyes of patients dead from nonrelated causes; the results were all negative. Therefore, no discrepancy was noticed between the examination of the blood and the vitreous humor. A description is made of a technique which uses a special trocar that enables the examination to be made without contamination with blood. The authors conclude that the determination of antibodies in vitreous humor is a choice to be considered as a postmortem examination because it can be easily obtained and its results are reliable.